speaker phasing

Here's the answer to your question about Boyle's Law (which you will ignore,
of course)...

PV = k assumes a constant temperature. If the temperature changes, then PV
changes. The relationship is no longer linear, and as the air trapped in the
cabinet is supposedly providing a significant part of the restoring force, the
cone's displacement will not be as linear. (Duh... Get it?)

This is what WDW is talking about when he says "As SF6 is an 'ideal gas', it
operates as an 'isothermal' spring, thus avoiding the problems with
'acoustic-suspension' loudspeakers that operated partially as an isothermal
and partially as an adiabatic system. Some designers seemed to lave little
knowledge of Boyles Law or the Laws of Thermodynamics."

There is no such thing as an ideal gas, so WDW is wrong on this particular
point. However, if SF6 is significantly closer to being an isothermal gas than
air is, * then what he says makes sense. QED.

Gotcha! Finally got ya!

You may now jump up and down, Rumplestiltskin, until you break through the
floor.

Here's the answer to your question about Boyle's Law (which you will ignore,
of course)...

PV = k assumes a constant temperature. If the temperature changes, then PV
changes. The relationship is no longer linear, and as the air trapped in the
cabinet is supposedly providing a significant part of the restoring force, the
cone's displacement will not be as linear. (Duh... Get it?)

This is what WDW is talking about when he says "As SF6 is an 'ideal gas', it
operates as an 'isothermal' spring, thus avoiding the problems with
'acoustic-suspension' loudspeakers that operated partially as an isothermal
and partially as an adiabatic system. Some designers seemed to lave little
knowledge of Boyles Law or the Laws of Thermodynamics."

There is no such thing as an ideal gas, so WDW is wrong on this particular
point. However, if SF6 is significantly closer to being an isothermal gas than
air is, * then what he says makes sense. QED.

Here's the answer to your question about Boyle's Law (which you will ignore,
of course)...

Click to expand...

PV = k assumes a constant temperature.

Click to expand...

** PV= k shows that it does not matter what the gas is - the same volume
changes produce the same pressure changes.

Uh... No it doesn't. k is temperature-dependent. Sorry about that,. but all
you have to do is look it up.
If a gas isn't perfect, then compressing (or rarefying it) changes its
temperature. This causes the pressure to change more than that caused by the
volume change. The result is a non-linear restoring force.

So the stiffness of an enclosed volume of gas is the same for all gasses.
The resonance frequency of a woofer will be unaffected by it.

Click to expand...

That's not what we're talking about, Mr Anuson.

Dunno who is the bigger LIAR.
You or the fuckwit you are mindlessly quoting.

"For a fixed amount of an ideal gas kept at a fixed temperature, pressure and
volume are inversely proportional."

Right? Now this one...

"Boyle's law is used to predict the result of introducing a change, in volume
and pressure only, to the initial state of a fixed quantity of gas. The before
and after volumes and pressures of the fixed amount of gas, where the before
and after temperatures are the same (heating or cooling will be required to
meet this condition), are related by the equation P1V1 = P2V2."

See the disclaimer? Compressing/expanding a non-ideal gas heats/cools it.
Assuming that both air and SF6 are non-ideal, this produces a non-linear
restoring force. SF6 is supposedly closer to ideal, so it should provide lower
distortion in a "true" acoustic-suspension system, where the gas provides a
big percentage of the restoring force.

You'd better give up, because I'm going to keep posting this until you do.

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